The present invention relates to fluid-operated wrenches, and particularly to such fluid-operated wrenches which have a rigid reciprocable driving element and a lever arm pivotably connected with the reciprocable driving element.
Fluid-operated wrenches of the above mentioned general type are known in the art. In the known fluid-operated wrenches one end of a rigid reciprocable driving element which generally is a piston rod of a piston in a cylinder-piston unit, is connected with one end of a lever arm which is arranged pivotably about its pivot axis. The connection is performed by means of a pivot pin which extends through the proximal ends of the piston rod and the lever arm. One of the disadvantages of the above described connection is that when the lever arm pivots under the action of the piston rod about its pivot axis, the end of the lever arm which is connected to the piston rod applies unwanted side loads to the piston rod. It is to be understood that this phenomenon is very undesirable and can lead to a premature wear or breakage of the respective parts.